1. Field of the Invention
The present invention relates to a magnetic recorder which prevents brown stain of the surface of the magnetic head.
2. Description of the Prior Art
In the field of magnetic recording, the high density of recording is realized by metallization of a magnetic recording medium and a magnetic head.
Magnetic recording mediums made of metal are used instead of magnetic recording mediums made from oxide magnetic powders such as Fe.sub.2 O.sub.3, Co--.gamma.Fe.sub.2 O.sub.3 or CrO.sub.2. For example, a magnetic recording medium made of magnetic metallic powders of a metal such as Co or Fe or an alloy such as Co-Fe (referred to as MP type magnetic recording medium), and a magnetic recording medium having a magnetic metallic thin film layer of metal such as Co, Ni or Fe or an alloy thereof (referred to as ME type magnetic recording medium are used).
On the other hand, a magnetic head having a magnetic core made from metal of Fe--Al--Si alloy (referred to called as Sendust) or Co--Nb--Zr--Ta amorphous alloy is used instead of a magnetic head made from ferrite.
In a magnetic recorder for high density recording, such a magnetic head is installed in a cylinder rotating at a predetermined speed and a magnetic tape is carried around the cylinder. However, the magnetic recorder has problems as mentioned below in various environments such as in a low humidity environment.
For example, a portion of the magnetic layer of the magnetic recording medium may peel off as the magnetic recording medium contacts the magnetic head. Such peeled-off pieces result in a stain on the magnetic head, and the output of the magnetic head made from metal is substantially degraded large extent. For example, if the magnetic tape is the color brown, a brown stain forms on the magnetic head.
Water content in air due to relative humidity provides a lubrication action so as to allow a magnetic tape to traverse a magnetic head smoothly. However, this contribution of the water content which provide lubrication of magnetic tape running over the magnetic head decreases at low humidity condition. This results to the direct contact of the magnetic tape with the magnetic head.
Japanese Patent laid open Publication 2-96996 discloses a magnetic recorder wherein a thermoelectric refrigeration element responsive to an external signal is provided between a magnetic head and a rotating cylinder in order to generate a substantially high humidity environment around the magnetic head in order to decrease contact noises or noises generated by the rubbing of the tape against the head.
However, there are problems with the action and the reliability of the thermoelectric refrigeration element. More specifically the a magnetic head cannot be cooled enough because the rotating cylinder is used as a heat sink of the exothermic side to prevent excessive heat radiation. Further, in a magnetic recorder wherein many magnetic heads are used, a space for cooling respective magnetic heads with respective refrigeration elements cannot be provided. It is also necessary to provide brushes for current terminals used to supply an electric current into the refrigeration element in the cylinder. However, if a sufficient number of current terminals of the brushes cannot be provided, the electrical contact of all terminals cannot be guaranteed because of dusts in the brushes.